CN-224231852-U - Self-adaptive current detection circuit

CN224231852UCN 224231852 UCN224231852 UCN 224231852UCN-224231852-U

Abstract

The application discloses a self-adaptive current detection circuit.A Hall current sensor is connected in series with an input original voltage line by a current-voltage conversion circuit, current signals are collected for conversion, and the converted voltage is output; the primary voltage conditioning circuit is used for conditioning the voltage signal after the current transformation based on the first group of rail-to-rail operational amplifiers; the second-stage voltage conditioning circuit is used for conditioning the voltage signal after the current transformation based on the second group of rail-to-rail operational amplifiers, wherein the amplification factor of the first-stage voltage conditioning circuit is larger than that of the second-stage voltage conditioning circuit; the AD conversion circuit is used for sampling the two conditioned voltage signals respectively, obtaining two current values after conversion by software, and comparing the two current values with a preset threshold value to obtain a final detection current value.

Inventors

ZENG FANG
LI HOUCHUN

Assignees

西安爱生技术集团有限公司

Dates

Publication Date: 20260512
Application Date: 20250430

Claims (6)

1. An adaptive current sensing circuit, comprising: The current-voltage conversion circuit, the primary voltage conditioning circuit, the secondary voltage conditioning circuit and the AD conversion circuit; the output of the current-voltage conversion circuit is respectively connected with the input of the primary voltage conditioning circuit and the input of the secondary voltage conditioning circuit, and the output of the primary voltage conditioning circuit and the output of the secondary voltage conditioning circuit are respectively connected with the two inputs of the AD conversion circuit; the current-voltage conversion circuit is used for collecting voltage signals based on the Hall current sensor; the primary voltage conditioning circuit is used for conditioning voltage signals based on a first group of rail-to-rail operational amplifiers to obtain first voltage signals; the second-stage voltage conditioning circuit is used for conditioning the voltage signals based on the second group of rail-to-rail operational amplifiers to obtain second voltage signals, wherein the amplification factor of the first-stage voltage conditioning circuit is larger than that of the second-stage voltage conditioning circuit; The AD conversion circuit is used for sampling the first voltage signal to obtain a first sampling signal, sampling the second voltage signal to obtain a second sampling signal, and comparing the converted first sampling signal and the converted second sampling signal with a preset current threshold value to obtain a detection current value.
2. The adaptive current detection circuit of claim 1, wherein the adaptive current detection circuit comprises: A hall current sensor, a capacitor C4, a capacitor C8, a capacitor C3, a capacitor C9, and a capacitor C10; the first end of the capacitor C4 is connected to the input original power supply ground end G, and the second end of the capacitor C is connected to the IP+ pin of the Hall current sensor and the original power supply input end V28; The first end of the capacitor C8 is connected to the IP+ pin of the Hall current sensor and the original power input end V28, and the second end of the capacitor C is connected to the IP-pin of the Hall current sensor; the first end of the capacitor C3 is connected to the VCC pin of the Hall current sensor and the power supply V5, and the second end of the capacitor C is connected to the digital ground GND; The first end of the capacitor C10 is connected to the NC pin of the Hall current sensor, and the second end of the capacitor C is connected with the digital ground GND; the first end of the capacitor C9 is connected to the V1OUT pin of the Hall current sensor, and the second end of the capacitor C is connected with the digital ground GND and the GND pin of the Hall current sensor.
3. The adaptive current sensing circuit of claim 1, wherein the adaptive current sensing circuit, the primary voltage conditioning circuit comprises: The first rail-to-rail operational amplifier, the second rail-to-rail operational amplifier, the resistors R1 to R7, the capacitor C1, the capacitor C2, the capacitor C5, the capacitor C6, the capacitor C7 and the voltage regulator V1; The first end of the resistor R1 is connected with the reference voltage Vref, and the second end of the resistor R2 is connected with the first end of the resistor R2 and the reverse input end of the first rail-to-rail operational amplifier; The second end of the resistor R2 is connected with the first end of the resistor R3, and the second end of the resistor R3 is connected with the output end of the first rail-to-rail operational amplifier; The first end of the capacitor C2 is connected with the reference voltage Vref, and the second end is grounded to the GND; The first end of the capacitor C1 is connected with the in-phase power supply voltage V5 of the first rail-to-rail operational amplifier, and the second end is grounded to GND; The non-inverting input end of the first rail-to-rail operational amplifier is connected to a VCC pin of the Hall current sensor through a resistor R7; The non-inverting input end of the second rail-to-rail operational amplifier is connected with the first end of the resistor R6, and the second end of the resistor R6 is grounded to GND; The first end of the resistor R4 is connected with the output end of the second rail-to-rail operational amplifier, and the second end of the resistor R4 is connected with the first input end of the AD conversion circuit; The first end of the capacitor C7 is connected with the non-inverting input end of the second rail-to-rail operational amplifier, and the second end is grounded GND; The cathode of the voltage stabilizing tube V1 is connected with the non-inverting input end of the second rail-to-rail operational amplifier, and the second end is grounded to GND; The first end of the capacitor C5 is connected with the second end of the fourth resistor R4, and the second ends are grounded GND; the first end of the capacitor C6 is connected to the second end of the fourth resistor R4, and the second ends are all grounded GND.
4. The adaptive current detection circuit of claim 1, wherein the adaptive current detection circuit, the secondary voltage conditioning circuit comprises: The third rail-to-rail operational amplifier, the fourth rail-to-rail operational amplifier, the resistors R8 to R14, the capacitors C11 to C16 and the voltage stabilizing tube V2; The first end of the resistor R8 is connected with the reference voltage Vref, the second end of the resistor R9 is connected with the first end of the resistor R9, and the reverse input end of the third rail-to-rail operational amplifier; The second end of the resistor R9 is connected with the first end of the resistor R10, and the second end of the resistor R10 is connected with the output end of the third rail-to-rail operational amplifier; a first end of the capacitor C12 is connected with the reference voltage Vref, and a second end of the capacitor C is grounded to GND; the first end of the capacitor C11 is connected with the in-phase power supply voltage V5 of the third rail-to-rail operational amplifier, and the second end of the capacitor C is grounded GND; The non-inverting input end of the third rail-to-rail operational amplifier is connected to a VCC pin of the Hall current sensor through a resistor R13; The first end of the resistor R11 is connected with the output end of the fourth rail-to-rail operational amplifier, and the second end of the resistor R is connected with the second input end of the AD conversion circuit; the first end of the resistor R14 is connected with the second end of the resistor R13, and the second end is grounded GND; the first end of the resistor R12 is connected with the output end of the third rail-to-rail operational amplifier, and the second end of the resistor R is connected with the non-inverting input end of the fourth rail-to-rail operational amplifier; The first end of the capacitor C15 is connected with the non-inverting input end of the fourth rail-to-rail operational amplifier, and the second end of the capacitor C is grounded GND; the cathode of the voltage stabilizing tube V2 is connected with the non-inverting input end of the fourth rail-to-rail operational amplifier, and the second end of the voltage stabilizing tube V2 is grounded to GND; the first end of the capacitor C13 is connected with the second end of the fourth resistor R11, and the second ends are grounded GND; The first ends of the capacitors C14 are connected with the second ends of the fourth resistors R11, and the second ends of the capacitors C are grounded GND; and a capacitor C16, the first end of which is connected to the resistor R13 and the V1OUT end of the Hall current sensor and the resistor R13, and the second end of which is connected to the second end of the resistor R14 and the ground GND.
5. The adaptive current detection circuit according to claim 1, wherein the adaptive current detection circuit, the AD conversion circuit includes: MCU, have 12 AD converters, and the AD converter carries out data transmission and storage through DMA.
6. A detection device having an adaptive current detection circuit according to any one of claims 1-5.

Description

Self-adaptive current detection circuit Technical Field The present application relates to the field of current detection, and in particular, to an adaptive current detection circuit and detection apparatus. Background The current detection circuit is widely used in various fields, and besides the measurement device is used for testing the current, almost every device is provided with the current detection circuit for the safety of the device. The current detection circuit is simpler, but the measurement device has higher requirements on the current measurement precision and the measurement range. How to have higher measurement accuracy under the condition of ensuring a large measurement range is an important condition for measuring the performance of measurement equipment. A common current measuring device has a multimeter which measures a small current and a large current by providing two wiring steps. When measuring small currents with large fluctuations, the gear is easily burned out, which results in a short circuit or an open circuit. Disclosure of Invention The application mainly aims to provide a self-adaptive current detection circuit and measuring equipment, and the self-adaptive current detection circuit aims to solve the technical problem of how to ensure higher measuring precision under the condition of a large measuring range. To achieve the above object, a first aspect of the present application provides an adaptive current detection circuit, comprising: The current-voltage conversion circuit, the primary voltage conditioning circuit, the secondary voltage conditioning circuit and the AD conversion circuit; the output of the current-voltage conversion circuit is respectively connected with the input of the primary voltage conditioning circuit and the input of the secondary voltage conditioning circuit, and the output of the primary voltage conditioning circuit and the output of the secondary voltage conditioning circuit are respectively connected with the two inputs of the AD conversion circuit; the current-voltage conversion circuit is used for collecting voltage signals based on the Hall current sensor; the primary voltage conditioning circuit is used for conditioning voltage signals based on a first group of rail-to-rail operational amplifiers to obtain first voltage signals; the second-stage voltage conditioning circuit is used for conditioning the voltage signals based on the second group of rail-to-rail operational amplifiers to obtain second voltage signals, wherein the amplification factor of the first-stage voltage conditioning circuit is larger than that of the second-stage voltage conditioning circuit; The AD conversion circuit is used for sampling the first voltage signal to obtain a first sampling signal, sampling the second voltage signal to obtain a second sampling signal, and comparing the converted first sampling signal and the converted second sampling signal with a preset current threshold value to obtain a detection current value. Optionally, the adaptive current detection circuit includes: A hall current sensor, a capacitor C4, a capacitor C8, a capacitor C3, a capacitor C9, and a capacitor C10; the first end of the capacitor C4 is connected to the original power supply ground end G, and the second end of the capacitor C is connected to the IP+ pin of the Hall current sensor and the original power supply input end V28; The first end of the capacitor C8 is connected to the IP+ pin of the Hall current sensor and the output end of the original power input end V28, and the second end of the capacitor C is connected to the IP-pin of the Hall current sensor; The first end of the capacitor C3 is connected to the VCC pin of the Hall current sensor and the output of the power supply V5, and the second end of the capacitor C is connected with the digital ground GND; The first end of the capacitor C10 is connected to the NC pin of the Hall current sensor, and the second end of the capacitor C is grounded to GND; The first end of the capacitor C9 is connected to the V1OUT pin of the Hall current sensor, and the second end of the capacitor C is grounded to GND and the GND pin of the Hall current sensor. Optionally, the adaptive current detection circuit, the primary voltage conditioning circuit includes: The first rail-to-rail operational amplifier, the second rail-to-rail operational amplifier, the resistors R1 to R7, the capacitor C1, the capacitor C2, the capacitor C5, the capacitor C6, the capacitor C7 and the voltage regulator V1; The first end of the resistor R1 is connected with the reference voltage Vref, and the second end of the resistor R2 is connected with the first end of the resistor R2 and the reverse input end of the first rail-to-rail operational amplifier; The second end of the resistor R2 is connected with the first end of the resistor R3, and the second end of the resistor R3 is connected with the output end of the first rail-to-rail operational amplifier; The firs